If a muscle cell’s sarcoplasmic reticulum had little to no Ca2+, could the muscle cell still produce an electrical impulse, and would the muscle cell still contract? Explain.

Q: What prevents cross-bridges from attaching to sites on the thinfilaments in a resting skeletal…

A: Muscles are the tissues able to contract in response to stimuli.

Q: Among the following which one is NOT the location of smooth muscle cells?

A: As the name suggests, smooth muscle cells do not any striations. They are narrow spindle shaped…

Q: What ion and ion channels does a muscle cell have?

A: A specialized tissue that originates from the mesodermal layer and helps in the locomotion of an…

Q: A student athelete measured his running performance on a treadmill and found the following data: 15…

A: There are two main types of skeletal muscle fibers. They are type I (slow-twitch muscle fibers) and…

Q: Myosin heads bend when attached to actin

A: Correct option is C  Myosin heads bend when attached to actin

Q: Why is Excitation Contraction Coupling important?

A: Muscles contraction  The contraction of muscle activated by the tension generating sites present in…

Q: Explain why skeletal muscle cells contain many mitochondria.

A: Mitochondria is a cell organelle found in the cytoplasm eukaryotic cell. It is a double…

Q: .The poison ouabain (wah-BAY-in), or arrow poison, blocks the Na+ K+pump. What effect would this…

A: Ouabain is also called the g-strophanthin. It is a toxic substance derived from a plant that was…

Q: Which region or organelle—cytosol, mitochondrion, or SR—contains the highest concentration of…

A: In a resting skeletal muscle cell, low amounts of calcium ions are present in the cytosol. The…

Q: The single-fiber twitch experiments shown here were generated by stimulating the muscle cell…

A: When a muscle is triggered by a single vibration, an action potential is generated that causes the…

Q: What is the function of myosin light-chain kinase in smooth muscle?

A: The muscular framework is an organ framework comprising of skeletal, smooth and heart muscles. It…

Q: Why would cardiac muscle cells and some smooth muscle cells.continue to contract even when their…

A: Human body has more than 600 muscles which perform many useful functions and help us in doing…

Q: Thick myofilaments consist mainly of the protein _____.

A: Thick myofilaments consist mainly of the protein called Myosin.

Q: Suppose a person had an unusual mutation in the troponin protein of his skeletal muscles, such that…

A: The muscular system is a system of muscles where muscles are connected to bones and also to envelope…

Q: myofibrils or sarcomeres present in smooth muscle fibers?

A: Myofibrils are the long filaments which are arranged parallel to each other to form muscle fibers.…

Q: Why do muscle cells use creatine phosphate insteadof glycolysis to supply ATP for the first few…

A: ATP or adenosine triphosphate provides the energy for muscle contraction.For ATP regeneration, three…

Q: Myofibis in muscle fibres are made up of repeating units of dark and light bonds called

A: Myofibril is a muscle cell that is shaped like a rod. Many chains of Myofibril bound together to…

Q: Which of the following is the smallest: muscle fiber, thick filament, or myofibril? Which is…

A: Myofibrils are made up of small structures known as Myofilaments. There are basically two main kinds…

Q: Describe the events by which depolarization of a smooth muscle cell results in contraction and…

A: Smooth muscle is a kind of muscle that is used by various systems to apply pressure on organs and…

Q: If you introduced a chemical into a muscle fiber that blocked the voltage-gated calcium channels in…

A: The muscles are the soft tissues found in the animals. They are made up of special types of…

Q: Describe the length-tension relationship in skeletal muscle fibers.

A: The skeleton muscle varies in shape, size, and arrangement of fibers. These range from small strands…

Q: Why does Skeletal muscle cells contain more mitochondria than other organelles?

A: A skeletal muscle cell is a multinucleate syncytium that forms by the fusion of hundreds of myoblast…

Q: If the blood flow to a skeletal muscle were markedly decreased, which types of motor units would…

A: Introduction: Small arteries and arterioles form the microcirculation unit and are innervated…

Q: A skeletal muscle can be stimulated, under laboratory conditions, with a supramaximal stimulus. Is…

A: As the nervous system produces electrical stimuli called an action potential, it passes through a…

Q: What effect does increasing the frequency of action potentials in askeletal muscle fiber have upon…

A: With alternative arrangements of light and dark band, skeletal muscles are striated muscles. They…

Q: Myosin motor proteins are NOT involved in which of the following?

A: option a not involved Regulating the mitotic organizing center MTOCs  Option b involved because…

Q: If a single twitch of a skeletal muscle fiber lasts 40 msec, what action potential stimulation…

A: In human physiology, skeletal muscle is defined as the vital organ of muscular system which is also…

Q: Unlike skeletal muscle smooth muscle Mayer spontaneously contract when it is. What feature of smooth…

A: Smooth muscle is a non-striated muscle, divided into two groups; single unit and multiunit smooth…

Q: What basic physiological properties do a nerve cell and a muscle cell have in common? Name a…

A: Basic physiological property that nerve cell and muscle cell have in common are excitability and…

Q: Calcium is the trigger for contraction of all muscle types. How does its binding site differ in…

A: In the human body, there are three types of muscles, skeletal muscles, cardiac muscles, and smooth…

Q: If ligand-gated K+ channels were to open in an unstimulated muscle fiber,how would this affect the…

A: The ligand-gated channels are those channels that open in response to the ligand which could be…

Q: As skeletal muscle shortens with contraction, the length of the I band remains constant as the…

A: Muscle contraction is defined as the process of stimulation of tension generation sites present…

Q: Explain how the length of a muscle fiber at the time it is stimulated to contract affects the…

A: Introduction:- The functional unit of striated muscle is the sarcomere. This is the most fundamental…

Q: If we need ATP for both contraction and relaxation, how would you explain why rigor mortis appears…

A: Rigor mortis is the onset of stiffness in the dead body several hours after the person dies. It is a…

Q: At what point during excitation contraction coupling does exocytosis play a role? Group of answer…

A: Excitation - contraction coupling in the skeletal muscle is the sequence of events through which the…

Q: Why calcium is important in skeletal muscle contraction?

A: All muscle filaments use Calcium ion (Ca2+) as their fundamental regulatory and signalling molecule.…

Q: Which type of myosin is found in contractile bundles?

A:

Q: why would skeletal muscle cell need so many nuclei?

A: Skeletal muscle is a striated muscle and it usually does not contract unless stimulated by the…

Q: Why will an increase in the strength of a stimulus cause an increase in the force of contraction in…

A: Stimulus: A stimulus in physiology is a change in the physical or chemical structure of an…

Q: and voltage-gated channels found?

A: Muscle cells,  are mostly known as myocytes,  they are the cells that make up the muscle tissue.

Q: How would muscle contractions be affected if ATP wascompletely depleted in a muscle fiber?

A: Myofibril is also referred to as muscle fibril. They are the rod-like constitutions of the muscle…

Q: The filaments of skeletal muscle are moved by free energy derived from the hydrolysis of ATP. During…

A: During anaerobic glycolysis, glucose is decomposed into lactic acid and releases energy. In the…

Q: what the Source of energy of actin, myosin and type II muscle fibers?

A: Actin and myosin are two types of proteins that form contractile filaments in muscle cells. Type II…

Q: Write note on the circled events of the excitation contraction coupling shown in the diagram below.…

A: The diagrammatic representation shows the process of cardiac excitation contraction coupling. This…

Q: How is a muscle cell excited and why does it lead to a contraction in the muscle?

A: Excitation for Muscle Contraction:  ∙ Nerve impulse advances arrival of Neurotransmitter…

Q: Calcium is released from the sarcoplasmic reticulum following death. Without available ATP, rigor…

A: Muscles are required in breathing, talking, running, walking, and anybody's movement. Actin and…

Q: e What would happen if the refractory period of a skeletal muscle fiber were abnormally prolonged…

A: Introduction Refractoriness is the ability of any object of autowave nature (particularly excitable…

Q: If you were to watch muscle tissue contract: Under a light microscope, would you see the muscle…

A: Muscles play a vital role in the force and motion of the body. They contain protein filaments of…

Muscle Action

A change in the body or a bodily organ as a result of its functioning is referred to as an action. Muscle action can be defined as the specific movement of a bodily part generated by the contraction of a muscle. The muscle proteins actin and myosin are the important contractile proteins involved in muscle action. Muscle contraction, in addition to movement, serves several other important functions in the body, including posture, heat generation, and joint stability. Muscle contraction maintains posture, which includes standing and sitting.